Jakob muller



J. MULLER ENGINE AIR COMPRESSOR.

APPLICATION FILED DEC, I8. 1917.

1,381, 133. Patented June 14, 1921;

Qwuewtoa JAKOB MfiLLER, or VELTHEIM, WITZERLAND, .ASSIGNOR TBUscn-sULzER anos. DIESEL ENGINE COMPANY, or sr. LOUIS, MISSOURI, aconronerron OF MISSOURI.

ENGINE AIR-COMPRESSOR.

p c t u er n t Patented June14, 1921.

Application filed December18, 917. SerialNo. 207,767.

ToaZZ whom it may concern- Be it known that I, Janos Mr'iLrnn, a citizenof the Re oublic of Switzerland, residing at Veltheim, bwitzerland, haveinvented the marine PIOPLllSlOIhhll as will be hereinafter.

made apparent to those skilled in this art;

Referring to the drawings Figure l is a vertical section of a threestagcair compressor as applied to an engine, and having stepped pistons andincorporating the present invention. pressor valves and interconnectingpassages are omitted from this figure, for convenience, and inasmuch astheir structure and relation forms no part of the invei'ition.

Fig. 2 is a top plan of the piston part of greatest area; and

Fig. 8 is an axial section through a part of the piston.

in Fig. 1 the cylinder structures desig nated 1 and 2 surmount the crankcase 3 which may be a part of the crank case of the combustion engine onwhich the co1npressor is used, and the stepped piston structures 4E and5 in said cylinders are trunk pistons operated by the connecting rod (5from a crank shaft 7 which latter may be the main crank shaft of theengine. Certain limitations in respect to the over-all height of marineengines, particularly submarine engines, prescribe a very short distanceof separation between the lower end of the cylinder structure and theengine crank shaft, which fact makes it desirable that the connectingrod shall extend upwardly into the piston trunk as far as possible inorder that it may have a maximum length under the conditions stated andthereby give a mini mum side thrust on the piston when in ac.- tion. Tothis and other ends the piston pin 8 of the connecting rod 6 is mounted,not in the side wall or trunk of the piston 5 as in the common design oftrunk piston, but in a separate member 9 centrally bolted to form of ashort cylindrical body with an mturnedattachmeht flange 10 at its upper'end and 1t, constitutesv what may be called a The usual comg theunderside of the face or end wall of the piston 5 at the junction of thelarge and small I diameters of the piston structure. Tllls separatemember desirably takes the.

false piston'trunk, being spaced from the wall of the trunk proper sothat it has no contact with the cylinder. At its lower end this falsetrunk bears/upon, but is not attached to the piston trunk proper,through the intervention of aspacing flange ring 11 which: ring may besecured either to the false or the proper trunk as will be evident butis hereshown as formed intcgrallywith the proper trunk. The piston pin 8is fitted and secured to the false trunk in the same manner as iscustomary with piston pins directly mountedin trunkpistons. That is tosay, 1t is mounted in the bosses 12 which are. formed integrally withthe falsetrunk. In-

asmuch as the false trunk isof less diameter than the trunk proper inwhich it is contained,,1t Wlll be apparent that the piston pin 8 iscorrespondingly shorter than would otherwise be necessary and is hencelighter. At the same tune the trunk wall of the pisten 5 may be cast ofuniform or regular sections throughout; it requires no reinforcingribbing since it has no bearing bosses,

such as 12, and it is not pierced by the piston pin, which latter factenables the said pin to be located as close to the piston face as thenecessary clearance for the connecting rod head will permit, withouttending to restrict the number of packing or piston rings 13 or toproduce a path of air lealcige through the piston pin hearing. Thelength of the connecting rod may thus be increased to a maximumconsistent with the dimensions of the other parts and adequate head roommay be provided within the crank case- The high pressure piston 4- ishollow and its interior opens into the false trunk and is utilized asclearance for the head of the connectingrod. 7

Through its connection to the piston face and its lateral bearing on theflange ring 11, the false trunk distributes the lateral thrust of theconnecting rod to the trunk proper and imparts the longitudinal thrustdirectly to the center of the face wall of the piston 5 and directly inline with the high pressure, smaller diameter, piston member 4. The latiteris centrally attached to the oppositeside of the face wall of piston5 by means of 81X double ended. screw studs 14, screwed into the flangeand projecting through the face wall of piston 5. The castellated nuts15, counter-sunk in the base flange ofpiston 4, are threaded onto theupper ends of these studs and thereby clamp all three parts rigidly andsecurely together and in leakproof manner. The nuts 15 are accessiblefrom the side, on removal of the. high pres-. sure cylinder structure 1,and when unscrewed oermit an easy and very convenient. wlthdrawal of thefalse trunk or the large piston, the false trunk. may be removed whilestill connected to the connecting rod 6 and,

the cylinder head side of said trunk piston for detachably securing saidconnection member thereto.

2. In an air compressor, having a stepped,

trunk piston structure, the combination with the connecting rod of saidstructure, of a false piston trunk secured to the piston structure atthe unct1on of the large and,

small diameters thereof and occupying the portion of larger diameter.

3. In an air compressor, having a stepped trunk piston, the combinationwith the connecting rod of said piston, of'a false piston trunk securedto the piston structure at the junction of the large and small diametersthereof and having a spaced lateral bearing on said structure adapted todistribute the side thrust of the connecting rod thereto.

4. In an air compressor, the combination vith a trunkpiston and theconnecting rod thereof, of a false trunk within the piston trunkcarrying the piston pin for the connecting rod and adapted to distributeside thrust of the connecting rod to said piston trunk, the false trunkbeing spaced f'om the valls of the latter adjacent the ends of thepiston pin.

5 Inan air compressor, the combination with a trunk piston andconnecting rod therefor, of a false trunk detachably secured to thecentral region of the end wall of said piston, and entirely inclosedtherein and laterally. spaced therefrom, the false trunk carrying thepiston pin for said connecting rod in a part thereof laterally spacedfrom the piston walls.

6. In an air compressor, the combination with a stepped trunk piston,the large and small diameter portions whereof are formed as separateparts, of. a false trunk contained within the part of larger diameterand carrying the piston pin and means for securing the said parts oflarge and small diameters together and to said false trunk.

7. In a device of the class described, the

combination with a trunk piston and coir necting rod therefor, of afalse trunk located centrally in the trunk piston and detach-' ablysecured at its ends to toe latter, the false trunk between its endsbeing laterally spaced from the walls of the trunk pistonv and in suchlaterally spaced portion carrying the piston pin for said connectingrod.

In testimony whereof I have signed this specification.

JAKOB B'IUIALE it.

